The present invention relates to a data collection apparatus for remote reading of utility meters and the like.
Due to the high personnel costs and possibility of error involved in manual reading of gas, water, electric and similar utility meters installed in individual homes, automatic systems have been developed which electrically read the meters via transmission lines. Such systems connect a main station located in the headquarters or branch of the utility company to the individual meters in the homes. It has been practiced in the art to embody the transmission lines as public telephone lines and provide the meters with means for responding to predetermined respective code signals applied to the telephone lines. In response to a code signal corresponding to itself, a particular meter will apply data signals to the telephone line representing the meter reading. The data signals are received by the main station and used to prepare the utility bill for the customer.
However, due to high costs and other problems, improved systems for remote reading of utility meters have been developed using separate transmission lines which are the property of the utility company. Such systems which have proven advantageous comprise three transmission lines which connect the remote stations to a main station. A remote station is provided to each utility meter and comprises an integrated three-wire motor counter. An electric motor drives the utility meter in dependence on the amount of utility consumed and opens and closes switch contacts which correspond to the meter reading.
A large number of these motor-counter units have been in service for such a long period of time that they must be replaced. Another important factor is the development of integrated meter units comprising electronic memory rather than mechanical counters, which are preferable from the view-points of economy of manufacture and reliability of operation. Rather than replace all of the motor-counter units at one time, it is preferable to gradually phase them out as they become unfit for service and replace them with the new electronic units. However, a remote data collection apparatus has not been proposed heretofore which can use the mechanical and electronic remote meter station units interchangeably.